Trace determination of Cr (VI) and Cr in tomato samples: risk assessment in a mining area in Iran

Abstract

Abstract To assess food safety, the determination of the highly toxic Chromium (VI) concentration in vegetables is important. Accurate and efficient determination of Cr(VI) in agricultural products, due to complex matrices, still remains a challenge. In this study, we aimed to determine the Cr(VI) concentration in tomatoes grown in farmlands, which is potentially contaminated by Pb and Zn mines and factories. We used an alkaline extraction at 80°C, for 5min containing 50 mM EDTA and dispersive liquid liquid miroextraction (DLLME) by spectrophotometric assay. Method validation, including spiking recoveries, showed satisfying results for Cr(VI) determination. Tomatoes were collected from two case studies: A) farmland, where the average concentrations of total Cr in soils was 73,775.51 µg kg− 1 and B) farmland with an average Chromium 24083.68 µg kg− 1. The average concentrations of Cr(VI) and total Cr in tomatoes from the contaminated case study A were 341.037 ± 55.2037 µg kg− 1 and 2539.731 ± 268.3714, respectively, while the lowest average Cr(VI) value was found to be 98.93917 ± 51.13807 and total Cr was 1243.09 ± 562.4392 µg kg− 1, attributed to case study B. In site(A), The total Cr in soil correlated with the Cr in tomatoes (r = 0.548), while a relatively low correlation was found for Cr (VI) in tomatoes (r = 0.309). The evaluation of the potential human health risks associated with tomatoes indicated that inhabitant children are at considerable non-carcinogenic and carcinogenic risks.